With the progress of computer image-processing techniques, a method of directly recording images on a photosensitive layer by irradiation corresponding to digital signals has recently been developed. Therefore, an intense interest has been shown toward a computer-to-plate (CTP) system in which images are directly formed on a photosensitive lithographic printing plate precursor, without outputting onto a silver salt mask film, by employing the method for a lithographic printing plate. The CTP system, which uses a high-output laser having a maximum intensity within a near infrared or infrared range as a light source for the irradiation, has, for example, the following advantages: images having high resolution can be obtained by exposure within a short time and the lithographic printing plate precursor used for the system can be handled in daylight. Regarding solid and semiconductor lasers capable of emitting infrared rays having a wavelength of 760 nm to 1,200 nm, a high-output and portable laser is available with ease.
As a lithographic printing plate precursor which can form images using a solid laser or semiconductor laser, JP-A-2002-296774, JP-A-2002-311577, and JP-A-2007-17948 disclose a lithographic printing plate precursor comprising a substrate and an image-recording layer provided thereon, in which the image-recording layer comprises a specific polymer having a perfluoroalkyl group.